Uncovering Ghost Ancestors in the Modern Human Genome

Researchers at UC Berkeley have developed a novel computational tool called TRACE to identify genetic material from extinct human lineages that have no surviving physical DNA. This method analyzes the genealogies of modern humans to uncover evidence of interbreeding with two previously unidentified "ghost" and "super-archaic" ancestors. The findings reveal that a ghost lineage contributed roughly 1% of the DNA found in all modern populations, while a super-archaic lineage mixed with Denisovans before reaching humans. These ancient genetic contributions are particularly prevalent in areas of the genome responsible for metabolism and immunity.